Methods for integrating and forming optically transparent devices on surfaces

ABSTRACT

An apparatus, system, and/or method are described to enable optically transparent reconfigurable integrated electrical components, such as antennas and RF circuits to be integrated into an optically transparent host platform, such as glass. In one embodiment, an Ag NW film may be configured as a transparent conductor for antennas and/or as interconnects for passive circuit components, such as capacitors or resistors. Ag NW may also be used as transmission lines and/or interconnect overlays for devices. A graphene film may also be configured as active channel material for making active RF devices, such as amplifiers and switches.

FIELD OF THE INVENTION

The present invention relates generally to integration and formation ofoptically transparent active and passive devices in or on surfaces.

BACKGROUND

Recent advances in and the increased number of Radio Frequency(RF)-based systems has escalated manufacturing efforts to designantennas more suitable for use with such systems. For example, antennasmay be found on vehicles or aircrafts. Several requirements are neededto meet antenna design constraints, including bandwidth and size.Moreover, antennas require adequate space to ensure optimal operationand performance. Designing antennas for vehicle or aircraft has beendifficult, as the design and aerodynamic constraints for such vehicles,make the space for an antenna limited. Accordingly, it would bepractical and economic to use existing space on vehicles or aircrafts todesign antennas to avoid space restrictions. One example of a usablesurface would be the glass surfaces on such vehicles.

Several examples of antennas have been researched, including passivetransparent antenna designs. Some examples include H. J. Song, T. Y.Hsu, D. F. Sievenpiper, H. P. Hsu, J. Schaffner, and E. Yasan, “A Methodfor Improving the Efficiency of Transparent Film Antennas,” IEEEAntennas and Wireless Propag. Lett., Vol. 7, 2008, pp. 753-756; J.Hautcoeur, F. Colombel, X. Castel, M. Himdi, and E. M. Cruz,“Performance of Transparent Monopole Antenna Versus Meshed Silver Layer(AgGL),” 2010 Proceeding of the Fourth European Conference on Antennasand Propagation (EuCAP), Barcelona, Apr. 12-16, 2010; A. Katsounaros, Y.Hao, N. Collings, and W. A. Crossland, “Optically TransparentUltra-Wideband Antenna,” Electronics Letts., Vol. 45, No. 14, Jul. 2,2009. pp. 722-723; and U.S. Pat. Nos. 7,847,753, B2,7,233,296 and7,427,961.

Additionally, optically transparent transistors have been described byA. Suresh, P. Wellenius, V. Baliga, H. Luo, L. M. Lunardi, and J. Muth,“Fast All-transparent Integrated Circuits Based On Indium Gallium ZincOxide Thin-film Transistors,” IEEE Electron Device Letts,” Vol. 31, No.4, April 2010, pp. 317-319; C.-T. Lee, W.-M. Shien, H.-Y. Lee, “Zno:AlBased Transparent Thin Film Transistors,” Proceedings of the 21st AnnualMeeting of the IEEE Lasers and Electro-Optics Society, 2008 LEOS,Acapulco, Nov. 9-18, 2008, pg. 65; and S. Ju, A. Facchetti, et al.,“Fabrication of Fully Transparent Nanowire transistors for Transparentand Flexible Electronics,” Nature Nanotechnology 2, pp. 378-384, 2007.These references do not describe antennas used with a transparentsubstrate.

Antennas have also been proposed with graphene. An example is describedin M. Dragoman, A. A. Muller, D. Dtragoman, F. Coccetti, and R. Plana,“Terahertz Antenna Based On Graphene,” J. of Applied Physics, Vol. 107,No. 10, 104313, 2010.

None of these examples describes an optically transparent RF functioningsurface. Therefore, a need exists for methods, systems, and devices thatinclude optically transparent active circuits with optically transparentpassive electromagnetic structures, such as antennas, for use in or on asurface.

SUMMARY

In one aspect, a device includes a transparent or substantiallytransparent substrate and a silver nanowire film. The silver nanowirefilm may be disposed to at least a portion of the substrate, and adielectric material may be applied to at least a portion of the silvernanowire film.

In another aspect, a method is described forming a passive electricaldevice that includes providing a transparent or substantiallytransparent substrate including a silver nanowire film, etching thesilver nanowire film; and coating a portion of the silver nanowire filmwith a dielectric material.

In yet another aspect, a device is disclosed that includes asubstantially transparent substrate, a gate electrode, a graphene film;and a plurality of contacts formed from silver nanowire on a portion ofthe graphene film. The device may include an antenna, a FrequencySelective Surface (FSS), a resistor, capacitor, or an inductor. The gateelectrode may be formed from gold, copper, Indium-tin Oxide (ITO), orIndium-zinc Oxide (IZO).

In yet another aspect, a method is disclosed that includes providing atransparent or substantially transparent substrate, forming a graphenefilm on a portion of the substrate, forming an electrical device, andforming a plurality of contacts on the graphene film from silvernanowire.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention(s) may be better understood by referring to the followingfigures. The components in the figures are not necessarily to scale,emphasis instead being placed upon illustrating the principles of theinvention. In the figures, like reference numerals designatecorresponding parts throughout the different views.

FIG. 1 illustrates a passive RF structure and an integrated component inan embodiment.

FIGS. 2( a)-2(c) illustrate coplanar waveguide (CPW) fed slot antennasin various embodiments.

FIG. 2( d) is a table showing maximum gain performance for the antennasof FIG. 2( a)-2(c).

FIGS. 3( a)-3(c) illustrate cross-sectional views of opticallytransparent components in various embodiments.

FIG. 4 illustrates a system and/or method of transferring graphene to asubstrate using a thermal release tape in an embodiment.

FIGS. 5( a) and 5(b) illustrate cross-sectional views of an opticallytransparent Field Effect Transistor (FET) in an embodiment.

FIG. 6 illustrates a cross-sectional view of an optically transparentgraphene active RF device integrated with optically transparent passiveRF structures in an embodiment.

DETAILED DESCRIPTION

Apparatus, systems, and/or methods are described to enable opticallytransparent reconfigurable integrated electrical components, such asantennas and RF circuits to be integrated into an optically transparenthost platform or transparent or substantially transparent substrate orsurface, such as glass or plexiglass. The disclosed structures may beconfigured with or used with RF-based systems. In one embodiment, asilver nanowire (Ag NW) film may be configured as a transparentconductor for antennas and/or as interconnects for passive circuitcomponents, such as capacitors, inductors, or resistors. Ag NW may alsobe used as transmission lines and/or interconnect overlays for devices.A graphene film may also be configured as an active channel material formaking active RF devices, such as amplifiers and switches.

The disclosed embodiments provide a completely or substantially completeoptically transparent RF front end that may be integrated into a glassor optically transparent host platform, which provides designflexibility for antennas and RF systems. Without implying a limitation,an RF front end may include components for receiving and/ortransmitting, an antenna interface, a low noise amplifier or aninterface to a digital baseband system, such as an analog to digitalconverter.

In one embodiment, a surface for antennas and RF circuits enablesreconfigurable antennas and RF active circuits to be integrated directlyinto or on the glass located around the vehicles, aircraft, buildings,and other structures or electronic devices. The disclosed methods mayexpand antenna design space to any glass on or around automobiles andaircraft. Various optically transparent RF structures, components andantennas may be formed into window glass and other glass structures.

The disclosed structures may lead to lower cost monolithic fabricationin which optically transparent passive and active structures are formedon an integrated circuit or chip. In one embodiment, the use ofmonolithic fabrication may form complete receivers on glass. Further,the demodulated signal output interface, e.g., interconnects and/orwiring, for a vehicle or aircraft may be configured for low frequencies.In regions away from the RF circuits, the disclosed structures may alsoserve as a solar reflective film that leads to a reduction of a thermalload of a vehicle, such as automotive vehicles. Other suitableapplications may include millimeter wave phased array antennas embeddedin or on glass and active electromagnetic (EM) shielding.

In one embodiment, the integration of optically transparent RFcomponents and RF front ends in/on optically non-opaque glass orplexiglass or any similar optically transparent host may be achieved forflat or curved surfaces. An optically transparent host platform orsurface, such as glass, may be used as a substrate for either an antennaor RF components/circuits.

In one embodiment, customized RF-functionality, such as radio frequencyselectivity, amplification, switching, and/or mixing, may be embedded inor on the optically transparent host platform. In one embodiment, thedisclosed antennas operate at microwave frequencies. In otherembodiments, the dimensions of the antenna may be modified to support oroperate at other frequencies.

In one embodiment, an optically transparent diversity antenna(s) may beintegrated in or on the host platform or surface by integratingoptically transparent switch(es) and antenna(s). A diversity antenna mayinclude two or more antennas configured to receive at least twoincoherent signals. An optically transparent, tunable frequencyselective surface may be integrated in or on the optically transparentplatform with optically transparent frequency tuning components andcircuits, such as a graphene metal insulator semiconductor (MIS)varactors or other MIS structures.

In one embodiment, an increase in effective conductivity of Ag NWantennas, transmission lines, or interconnects may be achieved byembedding a thin conductor, e.g., less than 10-12 micron wide conductorhaving a high conductivity of about 10⁷ S/m, along an edge of theantennas, transmission lines, or interconnects. Suitable materials forthe thin conductors may include gold, copper or similar material.Currents in the thin conductor may flow along the edges due to skineffects.

The disclosed embodiments and methods may increase effectiveconductivity of Ag NW or other transparent conductors by selectivelycontrolling local conductivity of the Ag NW or transparent conductors.The areas of high density current flows, such as along edges of aconductor or a slot, may be maintained by applying a high conductivityconductor, such as gold. Conductivity of the embedded conductive linesmay be about at least an order of magnitude more than that of a lossytransparent conductor to increase the effective conductivity.

In another embodiment, an increase in local conductivity may be achievedby selectively doping the local areas of graphene or transparentconductors. An increase in local conductivity may be achieved byselectively increasing a density of Ag NW or controlling a number ofgraphene layers or thickness of the transparent conductor films inselected local areas. In one embodiment, a graphene resistor is providedwith resistance control by controlling 1) defects in graphene, 2) dopingin graphene, or 3) a number of graphene layers.

The local selective conductive control methods may be applied toincrease an effective conductivity or decrease in effective resistanceof lossy conductors, such as transparent or opaque conductors. Themethods may also apply to any RF and non-RF structures includingtransmission lines in any configuration, e.g. a co-planar waveguide(CPW), microstrip, and/or strip, antennas or any radiating structures inany configurations, and/or interconnects and pads in any configurations.The described methods may provide Ag NW as transparent interconnects foractive RF devices, e.g., transistors, diodes, Ag NW antennas, or Ag NWtransmission lines, such as CPW, microstrip, or strip lines.

Transparent active devices on a substrate, such as glass, may requiredesired electrical, thermal, or mechanical properties. In oneembodiment, graphene may be used as an optically transparent materialand may include (1) high channel mobility, e.g., >1000 cm²/Vs, (2) highflexibility to enable transfer of the graphene film to curved surfaces,or (3) a high thermal conductivity providing sufficient thermaldissipation capability on glass.

FIG. 1 illustrates a passive RF structure 105 and an component 140integrated onto a substrate in an embodiment 100. The passive RFstructure 105, such as a Frequency Selective Surface (FSS), is showncoupled to and/or fabricated with an integrated component 140, such asan active antenna onto a substrate 110. The substrate 110 may be made ofglass. A portion of the substrate 110 may also be coated with Ag NW foruse as a solar reflective glass. An Ag NW film may be used as atransparent conductor for the component 140 or as an interconnect forpassive circuit components. A graphene film may be used as transparentactive channel material for making active RF devices, for example, atransistor. The component 140 may include a data out or intermediatefrequency (IF) out port and a graphene low noise amplifier 130.

FIGS. 2( a)-2(c) illustrate coplanar waveguide (CPW) fed slot antennasin various embodiments. Referring to FIG. 2( a), an antenna 200 is shownas an ideal reference antenna and includes a perfect electricalconductor (PEC) 225 and regions of glass 210 and 215. A PEC may be aconductor that does not produce losses and used to model antenna 200. Inone embodiment, gold or copper may be in a realization of the antenna200. In one embodiment, a realized gain may be approximately 2.7 dBi.The antenna 200 further includes an antenna feed point 205. In oneexample, the antenna may have a width of about 7.4 mm and height ofabout 4.3 mm. The antenna 200 may be configured with other heights andwidths depending on the application.

FIG. 2( b) illustrates an antenna 240 similar to antenna 200 including aportion 255 formed from Ag NW in place of the PEC with a metal edge 250formed along a slot. FIG. 2( c) shows an antenna 251 similar to antenna240 without the metal edge 250. FIG. 2( d) illustrates a table 260 ofelectromagnetic simulation results in terms of antenna gain for the CPWfed slot antennas of FIGS. 2( a)-2(c). Full electromagnetic simulationof the Ag NW antenna shows broadband performance at around 24 GHz with amaximum gain of better than 0 dBi at 24 GHz. In one embodiment, theantenna 240, 251 may be formed from copper or suitable conductingmaterial.

An Ag NW antenna may be formed in one embodiment as follows. Ag NW in asolution form may be applied or formed onto a host platform or surface.In one embodiment, the Ag NW may be sprayed or spin coated on a glasssubstrate, such as a Pyrex® glass, or similar substrate. The Ag NWcoated glass substrate may then be treated with acid to remove anyoxidation layer and to enhance conductivity. A capping layer of aluminumoxide (Al₂O₃), silicon dioxide (SiO₂), hafnium oxide (HfO₂), or anydielectric metal oxide may then be formed or applied to the Ag NW coatedglass by atomic layer deposition (ALD), which is then followed bysuitable lithography, etching and/or cleaning processes to patternantennas, wires and interconnects. In one embodiment, the capping layermay be applied to or formed on the Ag NW coated glass using spincoating, spray deposition, or chemical vapor deposition (CVD).

In one embodiment, the Ag NW coated glass may be etched prior to coatingwith a dielectric material. The etchant may be an acid-based etchant,and may be used without dilution. An example of a suitable etchant maybe found under the trade name Nickel etchant TFB available from theTransene Company, Inc., and may have chemical components including15-20% nitric acid, less than one percent potassium perfluoroalkylsulfonate, and water.

In one embodiment, a CPW fed slot type of Ag NW antenna may be designedand fabricated on glass for 24 GHz frequency band. Other suitableantenna designs may also be supported to achieve different frequencyranges.

In one embodiment shown in FIG. 2( b), an antenna efficiency of about50% or greater with transparent conductors having an opticaltransmittance of about 70% or more due to low conductivity (orequivalently a high sheet resistance) may be achieved. In oneembodiment, an Ag NW may be formed as the transparent conductor materialfor the antenna and graphene may be formed as a transparent activechannel for the RF circuits due to electrical, thermal and/or mechanicalproperties. In one embodiment, Ag NW film with the sheet resistance ofless than 10 ohm/square at 85% optical transmission, and graphene havingthe sheet resistance of 50 Ω/sq at 50% optical transmittance may beused.

In one embodiment, efficiency of antennas or passive RF structures orinterconnects made of Ag NW film may be increased by selectivelyenhancing the conductivity at edges of antenna radiator(s) or passive RFstructures, including transmission lines or interconnects by embeddingor adding thin strips, e.g. less than 10-12 microns, of higherconductivity metal where the currents are concentrated. In oneembodiment, the strips may be added or embedded near or around edge 250.This selective conductivity control approach may be also facilitated byselectively controlling the Ag NW layer density.

It has been determined that the selective conductivity control methodmay improve a gain of the 50 Ω/sq transparent conductor antenna with 90%optical transmittance from −8.1 dBi to −2.4 dBi. It has also beendetermined that for a 120 micron long CPW line made from Ag NW having asheet resistance of 5 ohm/sq, embedding 6 micrometer wide metalconductors along the edges of CPW line reduces a transmission loss from−0.88 dB to −0.025 dB, as shown in FIG. 2( b). An increase in antennagain may also be obtained by integrating a transparent transistoramplifier with the antenna in the monolithic fabrication process, whichmay form an active antenna. Other RF functionality such as switching andmixing may be fabricated into the RF substrate in a similar manner.

FIGS. 3( a)-3(c) illustrate cross-sectional views of opticallytransparent components in various embodiments. In one embodiment, anoptically transparent passive resistor 310, inductor 320, and/orcapacitor 330 components may be formed. The passive components may useAg NW for transparent interconnects.

Referring to FIG. 3( a), the resistor 310 may be formed on a glasssubstrate 315 with a layer of Ag NW 300 on a portion of the substrate315. Graphene 305 may be used as a resistance material for the resistorand a desired resistance may be obtained by introducing controlleddefects e.g. holes, slots, or similar structures, in the graphene, bycontrolling doping in graphene or controlling a number of graphenelayers, controlling a width and/or length of the Graphene.

FIG. 3( b) shows an inductor 320 formed on a glass substrate 325 and alayer of Ag NW 323 on a portion of the substrate 325. The inductor 320may be formed made from Ag NW using general spiral geometry. In oneembodiment, the inductor may be formed by an etching process. FIG. 3( c)shows a capacitor 330 which may be formed using silicon nitride (SiNx)or hafnium oxide (HfO₂) as a transparent dielectric material with Ag NWas ohmic contacts. Embedding of thin conductors to Ag NW may be appliedwhen forming the passive components in order to increase effectiveconductivity of the Ag NW.

Graphene may be grown on silicon (Si) and silicon carbide (SiC) wafer.The graphene film may be transferred onto a glass or transparentsubstrate or surface. The graphene film may be physically transferredonto a glass or transparent substrate by using a thermal release tape asa transfer medium. The graphene film may also be transferred using otherknown methods.

FIG. 4 illustrates a method of transferring graphene using a thermalrelease tape in an embodiment 400. The graphene layer 405 may be grownon a copper catalyst 410 on a substrate for graphene growth 415. Athermal release tape 420 may be applied to the graphene 405. The tape420 may be peeled from the substrate in a conventional manner andapplied to a substrate made from glass 430. Heat may be applied to thetape 420 at a suitable temperature to transfer the graphene to the glasssubstrate 430. One suitable temperature may be about 150° C.

FIGS. 5( a)-5(b) illustrate an example of a fully transparent transistorthat may be formed using graphene as an active channel layer and Ag NWas source and drain interconnect metal on top of a thin Ti/Au ohmiccontact metal. Thin copper, Indium-tin Oxide (ITO) or Indium-zinc Oxide(IZO) may be used as optically transparent gate metal. The gate metalmay have a thickness of tens of nanometers. FIGS. 5( a)-5(b) illustratecross-sectional views of an optically transparent Field EffectTransistor (FET) in an embodiment.

Referring to FIG. 5( a), a cross-sectional view of the bottom-gate FET510 having a source 504 and a drain 502, each formed from Ag NW and alayer of graphene 506 formed on a portion of an insulator 508. The FET510 may also include a gate 512 and a substrate 515. FIG. 5( b) shows across-sectional view of a top-gate FET 520 including a source 514 and adrain 512, each formed from Ag NW. The FET 520 further includes a gate516 formed on at least a portion of an insulator 518. A layer ofgraphene 521 is configured between the insulator 518 and a substrate525.

FIG. 6 illustrates a cross-sectional view of an optically transparentgraphene active RF device 615 integrated with optically transparentpassive RF structures in an embodiment 600. As shown, the active RFstructure 615 may be monolithically fabricated on a transparentsubstrate or substantially transparent substrate 625. The grapheneactive device 615 may represent the device shown in FIGS. 5( a)-(b). Agraphene layer 610 may be optionally left on top of an Ag NW layer 605to provide mechanical strength, thermal management, or a resistance toabrasion. The structure 600 may also include an Ag NW antenna 620, oneor more slots 622, which may be configured as part of the CPW-fed slotantenna structure, and one or more thin metal lines 621. Active RFcircuits generally require a thermal management capability. In oneembodiment, carbon-based graphene e.g., 4840-5300 W/mK may be used toprovide thermal dissipation of active RF circuits on or in the glasssubstrate.

The foregoing description of the preferred embodiments of the presentinvention has been presented for purposes of illustration anddescription. It is not intended to be exhaustive or to limit theinvention to the precise form or to exemplary embodiments disclosed.Obviously, many modifications and variations will be apparent topractitioners skilled in this art. Similarly, any process stepsdescribed might be interchangeable with other steps in order to achievethe same result. The embodiment was chosen and described in order tobest explain the principles of the invention and its best mode practicalapplication, thereby to enable others skilled in the art to understandthe invention for various embodiments and with various modifications asare suited to the particular use or implementation contemplated. It isintended that the scope of the invention be defined by the claimsappended hereto and their equivalents. Reference to an element in thesingular is not intended to mean “one and only one” unless explicitly sostated, but rather means “one or more.” Moreover, no element, component,nor method step in the present disclosure is intended to be dedicated tothe public regardless of whether the element, component, or method stepis explicitly recited in the following claims. No claim element hereinis to be construed under the provisions of 35 U.S.C. Sec. 112, sixthparagraph, unless the element is expressly recited using the phrase“means for . . . . ”

It should be understood that the figures illustrated in the attachments,which highlight the functionality and advantages of the presentinvention, are presented for example purposes only. The architecture ofthe present invention is sufficiently flexible and configurable, suchthat it may be utilized (and navigated) in ways other than that shown inthe accompanying figures.

Furthermore, the purpose of the foregoing Abstract is to enable the U.S.Patent and Trademark Office and the public generally, and especially thescientists, engineers and practitioners in the art who are not familiarwith patent or legal terms or phraseology, to determine quickly from acursory inspection the nature and essence of the technical disclosure ofthe application. The Abstract is not intended to be limiting as to thescope of the present invention in any way. It is also to be understoodthat the steps and processes recited in the claims need not be performedin the order presented.

The invention claimed is:
 1. A device, comprising: a non-opaquesubstrate; an optically transparent active device on the substrate,wherein the optically transparent active device comprises a plurality ofsilver nanowire contacts and a graphene channel; a silver nanowire film,the silver nanowire film disposed on at least a portion of thesubstrate; and a dielectric metal oxide disposed on at least a portionof the silver nanowire film; wherein the dielectric metal oxidecomprises one of aluminum oxide (Al₂O₃), silicon dioxide (SiO₂), andhafnium oxide (HfO₂).
 2. The device of claim 1 further comprising one ormore of an antenna, interconnects, transmission lines, a FrequencySelective Surface, a resistor, capacitor, and an inductor.
 3. The deviceof claim 1, wherein substrate is formed at least in part from one ofglass and plexiglass.
 4. The device of claim 2, wherein the antenna isconfigured to operate at one of RF, microwave and millimeter-wavefrequencies.
 5. The device of claim 2, wherein the antenna comprises oneof a silver nanowire film, a metal line and a slot formed on thesubstrate.
 6. The device of claim 2 further comprising a conductorembedded along an edge of one of the antenna, interconnect, andtransmission line.
 7. The device of claim 2, wherein the capacitorcomprises one of silicon nitride and hafnium oxide (HfO₂), and thesilver nanowire film is configured as an ohmic contact.
 8. A method offorming a passive electrical device, comprising: receiving a non-opaquesubstrate; forming graphene on a portion of the substrate; forming asilver nanowire film on the substrate; etching the silver nanowire film;and coating a portion of the silver nanowire film with a dielectricmaterial, wherein the dielectric material is not graphene.
 9. The methodof claim 8, wherein the etching the silver nanowire film furthercomprises etching the silver nanowire film with an etchant comprisingNickel etchant TFB.
 10. The method of claim 8, wherein the coating aportion comprises coating a portion of the silver nanowire film with oneof aluminum oxide (Al₂O₃), silicon dioxide (SiO₂), and hafnium oxide(HfO₂).
 11. The method of claim 8, wherein the electrical device furthercomprises one of an antenna, a Frequency Selective Surface, a resistor,capacitor, and an inductor.
 12. A device, comprising a non-opaquesubstrate; a gate electrode on the substrate; an insulator on the gateelectrode; a graphene film on the insulator; a source contact formedfrom silver nanowire on a first portion of the graphene film; and adrain contact formed from silver nanowire on a second portion of thegraphene film.
 13. The device of claim 12 further comprising one of anantenna, a Frequency Selective Surface, a resistor, capacitor, and aninductor.
 14. The device of claim 12, wherein the substrate isconfigured to operate with one of RF-based frequency, -selectivity,-amplification, -switching, and -mixing.
 15. The device of claim 12,wherein the gate electrode comprises one of gold, copper, Indium-tinOxide (ITO) and Indium-zinc Oxide (IZO).
 16. A method of forming anelectrical device, comprising: receiving a non-opaque substrate; forminga graphene film on a portion of the substrate; and forming a pluralityof contacts on the graphene film from silver nanowire.
 17. The method ofclaim 16, wherein the providing a substrate further comprises providinga substrate including one of glass and plexiglass.
 18. The method ofclaim 16 further comprising transferring the graphene to the substrateusing at least thermal release tape.
 19. The method of claim 16 furthercomprising forming one of a metal line and a slot in the substrate. 20.The method of claim 16 further comprising providing a gate formed fromone of gold, copper, Indium-tin Oxide (ITO) and Indium-zinc Oxide (IZO).21. The method of claim 16 further comprising forming one of an antenna,a Frequency Selective Surface, a resistor, capacitor, and an inductorfrom silver nanowire.
 22. A method of forming an electrical device,comprising: receiving a non-opaque substrate; forming a gate electrodeon a portion of the substrate; forming an insulator over the gateelectrode; forming a graphene film on a portion of the insulator;forming a source contact from silver nanowire on a first portion of thegraphene film; and forming a drain contact from silver nanowire on asecond portion of the graphene film.
 23. The method of claim 22, whereinthe providing a substrate further comprises providing a substrateincluding one of glass and plexiglass.
 24. The method of claim 22further comprising forming one of a metal line and a slot in thesubstrate.
 25. The method of claim 22 further comprising forming thegate electrode from one of gold, copper, Indium-tin Oxide (ITO) andIndium-zinc Oxide (IZO).
 26. The method of claim 22 further comprisingforming one of an antenna, a Frequency Selective Surface, a resistor,capacitor, and an inductor from silver nanowire.
 27. The device of claim1 wherein the optically transparent active device comprises: a gateelectrode on the substrate; an insulator on the gate electrode; agraphene layer on the insulator; a source contact formed from silvernanowire on a first portion of the graphene film and insulated from thegate by the insulator; and a drain contact formed from silver nanowireon a second portion of the graphene film and insulated from the gate bythe insulator.
 28. The device of claim 1 wherein the opticallytransparent active device comprises: a graphene layer on the substrate;an insulator on the graphene layer; a gate on the insulator; a sourcecontact formed from silver nanowire on a first portion of the graphenefilm and insulated from the gate by the insulator; and a drain contactformed from silver nanowire on a second portion of the graphene film andinsulated from the gate by the insulator.
 29. An electrical devicecomprising: a non-opaque substrate; a graphene layer on the substrate;an insulator on the graphene layer; a gate on the insulator; a sourcecontact comprising silver nanowire on a first portion of the graphenefilm and insulated from the gate by the insulator; and a drain contactcomprising silver nanowire on a second portion of the graphene film andinsulated from the gate by the insulator.
 30. The electrical device ofclaim 29 further comprising one of an antenna, a Frequency SelectiveSurface, a resistor, capacitor, and an inductor, the one of an antenna,a Frequency Selective Surface, a resistor, capacitor, and an inductorcomprising silver nanowire.
 31. A method of forming an electrical devicecomprising: receiving one of a substantially transparent and transparentsubstrate; forming a graphene layer on the substrate; forming aninsulator on the graphene layer; forming a gate on the insulator;forming a source contact formed from silver nanowire on a first portionof the graphene film and insulated from the gate by the insulator; andforming a drain contact formed from silver nanowire on a second portionof the graphene film and insulated from the gate by the insulator. 32.The method of claim 31 further comprising forming one of an antenna, aFrequency Selective Surface, a resistor, capacitor, and an inductor fromsilver nanowire.